Portland, PA 18351 Frost Dates
Portland, PA: when does the frost end?
Around 04/18 is the usual last spring frost, about 233 days away. Fall's first freeze usually shows up around 10/25, roughly 188 days after the last spring frost.
Portland sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 8 weeks until Portland's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Portland's last frost
04/18 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/05 and only about 1 year in 10 sees frost after that.
Portland against the rest of the dataset
At roughly 188 frost-free days, Portland places 22,164 of 40,283 ZIP codes in this dataset. Within PA, it ranks 599 of 2,088.
Learn more
Before leaning on 18351's figures: local microclimates explains what one yard in Portland can differ from the 18351 normal, while zone vs. frost date explains why Zone 6b and Portland's frost date answer different questions.